part_subject: "NATIONAL PRIMARY DRINKING WATER REGULATIONS"
subpart_code: "T"
subpart_subject: "Enhanced Filtration and Disinfection—Systems Serving Fewer Than 10,000 People"
section_number: "141.535"
section_subject: "What if my system uses chloramines, ozone, or chlorine dioxide for primary disinfection?"
cfr_reference: "40 CFR 141.535"
title_name: "Title 40"
title_subject: "Protection of Environment"
parts_covered: "Parts 136 to 149"
revised_date: "Revised as of July 1, 2019"
publication_date: "As of July 1, 2019"
contains_description: "Containing a codification of documents of general applicability and future effect"
publication_info: "Published by the Office of the Federal Register National Archives and Records Administration as a Special Edition of the Federal Register"
---
If your system uses chloramines, ozone, or chlorine dioxide for primary disinfection, you must also calculate the logs of inactivation for viruses and develop an additional disinfection profile for viruses using methods approved by the State.